Objective To determine the minimal local analgesic dose (MLAD) of hypobaric levobupivacaine in elderly patients undergoing spinal anesthesia during lower limb surgery. Methods A total of 25 patients underwent spinal anesthesia with hypobaric levobupivacaine during lower limb surgery. The initial dose of levobupivaeaine was 7.50 mg for the first patient. The dose for next patient was added by 0.25 mg if the level of sensory block was lower than that of T10, conversely the dose was subtracted by 0.25 mg. The MLAD of hypobaric levobupivacaine was calculated with up-and-down sequential experiment according to Dixon-Messay method. Results The MLAD of hypobaric levobupivacaine were 6.67 mg (95% confidence interval: 6.34-7.25). The anesthesia effects of all patients were good. The degree of motor blockade of the healthy leg was less than another leg.The intraoperative and postoperative complications rates associated with spinal anesthesia were low.Conclusions The MLAD of hypobaric levobupivacaine is 6.67 mg in elderly patients undergoing spinal anesthesia during unilateral lower limb surgery.

Objective:To summarize the clinical features and experience in diagnosis and treatment of subglottic cysts in children.Methods:The clinical data of 5 children with subglottic cysts admitted in Qilu Children′s Hospital of Shandong University from April 2018 to June 2019 were retrospectively analyzed.Results:Among the 5 patients, 2 cases were premature infants and 3 cases were full term infants.All patients had an endotracheal intubation history.One patient was asymptomatic.Four patients had laryngeal stridor, 2 cases of whom were accompanied by hoarseness and dyspnea.These 2 patients were used to be misdiagnosed with laryngomalacia, laryngitis, etc.Bronchoscopy revealed subglottic gray-white cyst-like lesions, and enhanced CT showed low density without enhancement.All patients were treated with laser and forceps, and bronchoscope was applied in the follow up period for 5-12 weeks.There was no recurrence or subglottic stenosis.Conclusions:Laryngeal stridor in children with a history of endotracheal intubation must be examined by bronchoscopy in time to find out whether there is subglottic cysts.Laser therapy is an effective treatment for subglottic cysts.

The clinical data of 4 children with congenital absence of tracheal cartilage ring in Qilu Children′s Hospital of Shandong University from November 2017 to August 2019 were retrospectively analyzed.The age of the 4 cases was from 2 months to 1 year.One case had no obvious symptoms after birth, and then had repeated wheezing attacks for 3 times.Another 3 cases had symptoms after birth, such as throat ringing, repeated cough and asthma.Bronchoscopy in 4 cases indicated that the local lumen of trachea was round and centripetal stenosis, but the body of bronchoscope could pass smoothly, and no cartilage structure was found in the wall of trachea.Among them, 3 cases of chest enhanced CT examination displayed local and hourglass-like tracheal stenosis, without vascular ring malformation.All the 4 cases were treated by operation, of which 3 cases recovered well and 1 case died of severe infection after operation.

Objective To investigate the impacts of midazolam on the proliferation,migration and invasion of breast cancer MDA-MD-231 cells and its regulation on cyclic adenosine monophosphate(cAMP)/protein kinase A(PKA)/cAMP response element binding protein(CREB)signaling pathway.Methods MDA-MD-231 cells were cultured in vitro and grouped into control group,midazolam L group,midazolam M group,midazolam H group,and midazolam H+Sp-cAMPS group.Midazolam L group,midazolam M group,midazolam H group were treated with 5μmol/L,10μmol/L,and 20μmol/L of midazolam,respectively,midazolam H+Sp-cAMPS group was added with 20μmol/L of midazolam+10μmol/L of Sp-cAMPS 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide(MTT)assay was applied to detect cell proliferation;The migration ability was detected by cell scratch test;Transwell test was applied to determine the invasion ability of cells;Cell apoptosis was detected by flow cytometry;The expression level of cAMP was detected by enzyme-linked immunosorbent assay(ELISA);Western blot was applied to verify the expression of phosphorylated(p-)PKA/PKA,p-CREB/CREB protein.Results Compared with control group,the cells in midazolam L group,midazolam M group,midazolam H group showed apoptosis,the apoptosis rate was obviously increased,the cell proliferation,migration and invasion abilities and the expression levels of cAMP,p-PKA/PKA,p-CREB/CREB proteins were obviously decreased(P<0.05);Compared with midazolam H group,midazolam H+Sp-cAMPS group had good cell growth,obviously reduced apoptosis rate,and obviously increased cell proliferation,migration and invasion abilities,and the expression levels of cAMP,p-PKA/PKA,p-CREB/CREB proteins(P<0.05).Conclusion Midazolam may inhibit the proliferation,migration and invasion of breast cancer cells by inhibiting the activation of cAMP/PKA/CREB signaling pathway.